Read the docs
TI-2022-06052 Aliases CVE-2022-21676GHSA-273r-mgr4-v34f

Uncaught Exception in engine.io

Priority MEDIUM 44CWE-754Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

Engine.IO is the implementation of transport-based cross-browser/cross-device bi-directional communication layer for Socket.IO. A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process. This impacts all the users of the `engine.io` package starting from version `4.0.0`, including those who uses depending packages like `socket.io`. Versions prior to `4.0.0` are not impacted. A fix has been released for each major branch, namely `4.1.2` for the `4.x.x` branch, `5.2.1` for the `5.x.x` branch, and `6.1.1` for the `6.x.x` branch. There is no known workaround except upgrading to a safe version.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02851 86th percentileScored 2026-11-07
Fix Fixed engine.io (socketio): 4.1.2, 5.2.1, 6.1.1engine.io (npm): 4.1.2, 5.2.1, 6.1.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
socketioengine.io4.0.0 to before 4.1.2; 5.0.0 to before 5.2.1; 6.0.0 to before 6.1.14.1.2, 5.2.1, 6.1.1Patch availableCNA
—engine.io (npm)4.0.0 to before 4.1.24.1.2Patch availableGHSA-273r-mgr4-v34f
—engine.io (npm)5.0.0 to before 5.2.15.2.1Patch availableGHSA-273r-mgr4-v34f
—engine.io (npm)6.0.0 to before 6.1.16.1.1Patch availableGHSA-273r-mgr4-v34f
  • engine.io Vendorsocketio Affected 4.0.0 to before 4.1.2; 5.0.0 to before 5.2.1; 6.0.0 to before 6.1.1 Fixed in 4.1.2, 5.2.1, 6.1.1 Patch available CNA
  • engine.io (npm) Vendor— Affected 4.0.0 to before 4.1.2 Fixed in 4.1.2 Patch available GHSA-273r-mgr4-v34f
  • engine.io (npm) Vendor— Affected 5.0.0 to before 5.2.1 Fixed in 5.2.1 Patch available GHSA-273r-mgr4-v34f
  • engine.io (npm) Vendor— Affected 6.0.0 to before 6.1.1 Fixed in 6.1.1 Patch available GHSA-273r-mgr4-v34f

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:socket:engine.io:*:*:*:*:*:node.js:*:*4.0.0 to before 4.1.2; 5.0.0 to before 5.2.1; 6.0.0 to before 6.1.1Vulnerablesocketio
  • cpe:2.3:a:socket:engine.io:*:*:*:*:*:node.js:*:* Versions 4.0.0 to before 4.1.2; 5.0.0 to before 5.2.1; 6.0.0 to before 6.1.1 Vulnerable ·socketio

Remediation

  • Fix · CNA engine.io (socketio) Fixed in 4.1.2, 5.2.1, 6.1.1
  • Fix · GHSA-273r-mgr4-v34f engine.io (npm) Fixed in 4.1.2 Advisory →
  • Fix · GHSA-273r-mgr4-v34f engine.io (npm) Fixed in 5.2.1 Advisory →
  • Fix · GHSA-273r-mgr4-v34f engine.io (npm) Fixed in 6.1.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2022-21676
  2. 2026-10-03 Alias added: GHSA-273r-mgr4-v34f

References

Patch 3

Advisory 6

Other 2

  • TI-2022-20281 Uncaught exception in engine.io CVSS 3.1HIGH 7.1
  • TI-2026-42594 Socket.IO: Engine.IO Polling Transport Connection Exhaustion CVSS 3.1HIGH 7.5
  • TI-2026-42593 Socket.IO: Engine.IO WebTransport SID DoS CVSS 3.1HIGH 7.5
  • TI-2020-18427 Engine.IO before 4.0.0 allows attackers to cause a denial of service (resource… CVSS 3.1HIGH 7.5
  • TI-2023-14835 Uncaught exception in engine.io CVSS 3.1MEDIUM 6.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences